If you're having trouble with BBM whereby the display pictures of your contacts are blank then here are some fixes:
Upgrade / downgrade Blackberry Messenger (BBM)
This issue often arises when users are on different versions of BBM. Try upgrading or downgrading BBM.
Upgrade the phone's Operating System (OS)
An OS update fixes this issue a lot of the time. See how to upgrade / update Blackberry OS or how to upgrade / update Android OS
Remove the battery for 1 minute then slot it back in. This will help end then restart all processes
Uninstall then Reinstall
Uninstall BBM, restart the phone then reinstall.
Request for service books
Go to home screen > Advanced Options > Host
Routing Table > Press the Menu key > Click Register Now > Wait for a confirmation
message > When the service books are sent,
restart the phone.
Grant adequate permissions
Go to Home screen > Options> Applications > Search for blackberry messenger > Edit permissions > Allow all of the options (connections, interactions, user data)